import { ElementRef, NgZone, OnInit } from '@angular/core';
import { Observable } from 'rxjs';
export declare class NgbModalBackdrop implements OnInit {
    private _el;
    private _zone;
    animation: boolean;
    backdropClass: string;
    constructor(_el: ElementRef<HTMLElement>, _zone: NgZone);
    ngOnInit(): void;
    hide(): Observable<void>;
}